SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '58e3d8d3d4a40badce5b6e92f334947c54153e066f43a38ed2e5d7274f09e128' 
  AND token = '6FJOAOVNTDu3iinWwYfWpRIfFkgvRcBb1vit9uwHS2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}